Compound for tempering steel



UNITED STATES PATENT OFFICE.

ALEXANDER H. SIEGFRIED, OF SELINS GROVE, PENNSYLVANIA.

COMPOUND FOR TEMPERING STEEL.

SPECIFICATION forming part of Letters Patent No. 257,248, dated May 2, 1882.

v Application filed September 24, 1681. (No specimens.)

T 0 all whom it may concern:

Be it known that LAALEXANDER H. SlEG- FRIED, of Selins Grove, in the county of Snyder and State of Pennsylvania, have invented certain Improvementsin Compounds for Tempering Stecl,of which the followingis a specification.

My invention relates to an improved compound for use in preparing and tempering. steel.

In making use of my invention I first prepare a compound consisting of salt, four and a half pounds; sulphate of copper, three-fourths of a pound; soda-ash, one and one-halfpound; sal-ammoniac, one pound; oxide of manganese, three-fourths of a pound sulphate of iron, three-fourths of a pound; nitrate of potassa, one-half of a pound. These ingredients are pulverized and thoroughly intermingled to produce a homogeneous mass. The steel to be treated is heated to a red heat and the compound applied thereto, after which the steel is returned to the fire and heated to aproper degree for working, then withdrawn and-worked on the anvil into the required shape. This operation is repeated until the tool is finished and ready for tempering, when it is heated to a cherry-red heat, the compound applied, and the tool subsequently tempered to give it the desired degree of hardness in the usual way.

I find that by means of the compound and the 0 treatment above described I-am enabled to give the cutting-tool a great degree of hardness combined with great strength and tough ness. 7

While it is preferred to adhere to the pro portions stated, they may be modified to a limited extent without seriously affecting the action of the compound.

The heating of metal and the application of the compound thereto may be repeated any desired number of times, steel which contains an excess of carbon reqnirin g a more thorough application of the compound than the steels in which the percentage of carbon is smaller.

Having thus described my invention, what I claim is- The compound for tempering steel, consisting of salt, sulphate of copper, soda-ash, sal-am moniac, oxide of man ganese, sulphate of iron, and nitrate of potassa,in substantially the propor- 5o tions specified.

ALEXANDER IlIRAllI SIEGFRIED.

Witnesses:

GEORGE EBY, VAL. Bone. 

